An aminopeptidase which cleaves the Tyr-Gly bond of Met-enkephalin was isolated from rat brain membranes. Various neuropeptides including ACTH-(1-24), ACTH-(1-10), somatostatin, Substance P and β-endorphin can inhibit this reaction with IC50 values of 0.7, 1.1, 2.1, 2.1 and 14.0 μM, respectively ACTH-(18-39) and bradykinin do not affect Met-enkephalin breakdown by this enzyme. The possibility is raised that these neuropeptides may regulate enkephalin and other neuropeptide levels in the brain by controlling their degradation under physiological conditions.
ASJC Scopus subject areas
- Endocrine and Autonomic Systems
- Cellular and Molecular Neuroscience